Since the end of the Cold War,
the US Navy has had an increasing interest
in continental shelves and slopes as
operational areas. To work in such areas
requires a good understanding of ocean
acoustics, coastal physical oceanography,
and, in the modern era, autonomous
underwater vehicle (AUV) operations.
Each area presents challenges for both
the scientist and the Navy. In physical
oceanography, a complex interplay
among winds, rivers, tides, and local
bathymetry drives a non-stationary, shelf-break
front and the nonlinear internal
wave (NLIW) field. These strongly
affect acoustic systems but are not
adequately understood. A key oceanographic
challenge is to model the fully
four-dimensional ocean from the large-scale
circulation down to fine scales,
which include NLIW packets, internal
tides, jets, and density fronts. Both Navy
acoustics systems and Navy operations
need the “local ocean weather” as
well as the “ocean climate” as part of
the routine forecast, but the former is
not yet available.